1. Field
The present disclosure relates generally to energy and, in particular, to energy harvesting devices. Still more particularly, the present disclosure relates to a method and apparatus for generating electrical energy from thermal energy using thermoelectric energy harvesting devices.
2. Background
Electrical devices are often used in different platforms to perform various functions. For example, sensors, lighting elements, routers, switches, and/or other types of devices may be present on an aircraft. These devices use electrical power to function. Wires are typically used to connect these devices to power sources. Additionally, batteries also may be used with these types of devices.
The use of wiring is often undesirable. Wiring increases the cost to design, install, maintain, and upgrade devices. When a device uses a battery, the battery has a size selected to sufficiently power the device for some desired period of time. Further, these batteries may need replacement and/or recharging periodically. Further, the cost and maintenance for batteries may be greater than desired.
One solution involves using energy harvesting devices. Energy harvesting devices are hardware devices that generate energy from a source external to the hardware devices. For example, these external sources may be solar power, thermal energy, wind energy, salinity gradients, kinetic energy, and/or other suitable types of sources. Energy harvesting devices use these sources and generate electrical energy for use by other devices. For example, energy harvesting devices may be used to generate energy for electrical devices.
One example of an energy harvesting device is a solar cell. Solar cells convert light into electrical energy. These devices generate electrical energy in the form of an electrical current that may be stored in a battery for later use or may be used directly by another device. When batteries are used for storage, these batteries may be smaller than when the electrical devices rely on a battery as the only source of power.
Other types of energy harvesting devices include thermoelectric energy harvesting devices. These types of devices use temperature gradients to generate electrical energy. As another example, vibrational energy may be converted by cantilevered piezoelectric beams into electrical currents.
These types of devices are particularly useful with electronic devices that may need batteries or wired connections to electrical power sources. Energy harvesting devices, however, may still take up more space and add more complexity or cost than desired.
Therefore, it would be advantageous to have a method and apparatus that takes into account at least some of the issues discussed above, as well as possibly other issues.